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A175767 List of pairs of "twin numbers": Omega(n) = Omega(n - 2^Omega(n)), where Omega is A001222. 0

%I

%S 3,5,5,7,6,10,11,13,10,14,17,19,12,20,21,25,22,26,20,28,29,31,34,38,

%T 35,39,24,40,41,43,42,50,44,52,51,55,40,56,59,61,58,62,65,69,71,73,68,

%U 76,70,78,48,80,82,86,87,91,91,95,84,100,101,103,88,104,107,109,102,110,80,112,111

%N List of pairs of "twin numbers": Omega(n) = Omega(n - 2^Omega(n)), where Omega is A001222.

%C The k-primes = numbers that are divisible by exactly k primes (counted with multiplicity).

%F a(2n+1) = A175766(n) = a(2n) + 2^A001222(a(2n+1)).

%e "Twin numbers" are (3, 5), (5, 7), (6, 10), (11, 13), (10, 14), (17, 19), (12, 20), (21, 25), (22, 26), (20, 28), (29, 31), (34, 38), (35, 39), (24, 40), (41, 43), (42, 50), (44, 52), (51, 55), (40, 56), (59, 61), (58, 62), (65, 69), (71, 73), ...

%Y Cf. A175766, A001222, A077800, A175612, A175765.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, Sep 01 2010

%E Rewritten by _Charles R Greathouse IV_, Sep 03 2010

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Last modified May 21 00:41 EDT 2019. Contains 323427 sequences. (Running on oeis4.)